Elevated serum myeloperoxidase activities are significantly associated with the prevalence of ACS and High LDL-C levels in CHD patients.

Aim: Recent researches have shown that myeloperoxidase (MPO) is a potential inflammatory risk factor for coronary heart disease (CHD). In the present study, the possible associations of MPO with acute coronary syndrome (ACS), low density lipoprotein cholesterol (LDL-C) and other risk factors in CHD patients were investigated. Methods: Five hundred thirty-six CHD patients [363 ACS and 173 stable angina pectoris (SAP)] and 181 non-CHD patients confirmed by coronary angiography were enrolled in this study. The association study was performed by logistic regression analysis. Results: ACS patients had significantly higher MPO activities than SAP and non-CHD patients (p< 0.001). The area under the receiver operating characteristic (ROC) curve of MPO for diagnosing ACS was 0.84 (95% CI: 0.80-0.88, p< 0.001). The optimal cut-off value (sensitivity; specificity) of MPO was 164.77 ng/mL (79.1% and 82.1%). LDL-C (III versus I tertile, OR: 3.24, 95% CI: 1.67-6.29, p=0.001) and ACS (yes versus no, OR 2.74, 95% CI: 1.71-4.39, p<0.001) were significantly associated with elevated serum MPO activities, which had the highest odds ratio in quantitative and qualitative variables, respectively. There were significant increase trends in the prevalence of ACS and high LDL-C levels from I to III MPO tertile, which were 46.4% and 8.9% for I, 68.0% and 31.5% for II, 88.8% and 59.8% for III tertile, respectively (p< 0.001). Conclusion: The present study provides epidemiological evidence that elevated serum MPO activities are significantly associated with the prevalence of ACS and high LDL-C levels in CHD patients, and MPO may be a potential early warning marker for ACS.